Improve DEV performance in Chrome

[gaearon]

This consistently improves DEV performance in Chrome.

Before this change:

create 10k rows: 7861
update 1k rows: 1405
update 1k rows: 1337
update 1k rows: 1373
update 1k rows: 1340
update 1k rows: 1381
clear 10k rows: 1603

create 10k rows: 7799
update 1k rows: 1391
update 1k rows: 1339
update 1k rows: 1324
update 1k rows: 1338
clear 10k rows: 1567

After this change:

create 10k rows: 6460
update 1k rows: 1312
update 1k rows: 1237
update 1k rows: 1231
update 1k rows: 1263
update 1k rows: 1248
clear 10k rows: 1083

create 10k rows: 6326
update 1k rows: 1298
update 1k rows: 1233
update 1k rows: 1245
update 1k rows: 536
update 1k rows: 1058
update 1k rows: 1299
clear 10k rows: 1104

This only seems to help DEV in Chrome. I did not observe any significant difference in PROD in Chrome, or in either build in Firefox or Safari.

Normally it would be too much dogscience but I feel the wins for Chrome DEV (most common use case) are significant, they are consistently reproducible, and it kinda makes sense to use numbers anyway.

[vitkarpov]

I did not observe any significant difference in PROD

Kinda weird. Is Uglifyjs used for building or some another tool?

[sophiebits]

Sounds good to me. Agree it's weird that prod mode is no faster.

[vitkarpov]

it kinda makes sense to use numbers anyway.

@gaearon Do you think it really makes sense? Actually, folks always use prod version in the wild.

[gaearon]

Kinda weird. Is Uglifyjs used for building or some another tool?

Yes, I uglified during the tests.

@gaearon Do you think it really makes sense? Actually, folks always use prod version in the wild.

As I said earlier this doesn’t have any downsides in production so I’m not sure what you are worried about.

I’m saying it “makes sense” because both these fields are numbers anyway so 0 makes more sense than null for resetting them. It’s nice that fixing this also improves perf in DEV mode in Chrome.

[vitkarpov]

these fields are numbers anyway so 0 makes more sense than null for resetting them

That's point! Agreed.